JP2009048928A - Rubber plug, and waterproof connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber plug and a waterproof connector high in sealing characteristics. <P>SOLUTION: The rubber plug 10 is equipped with a water stop part 12 having a portion to be tightly contactable with the inner peripheral face of a cavity 91 and the outer peripheral face of an electric wire 50, and an extended part 13 which is arranged straddling over the inside and the outside of the cavity 91, and which has the inner peripheral face to be tightly contactable in the axial direction with the outer peripheral face of the electric wire 50, and has a linear outer peripheral face parallel with this inner peripheral face. At the boundary between the water stop part 12 and the extended part 13, a first recessed part 21 is recessed and formed in the outer peripheral face, and at a portion positioned outside of the cavity 91 out of the extended part 13, a second recessed part 22 is recessed and formed in both inner and outer peripheral faces. When the electric wire 50 is bent, an opening edge of the cavity 91 is interfered with the outer peripheral face of the extended part 13. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rubber plug and a waterproof connector.

The rubber plug attached to the waterproof connector plays a role of preventing water from entering the cavity by being sandwiched between the inner peripheral surface of the cavity of the connector housing and the outer peripheral surface of the electric wire. For example, the device described in Patent Document 1 has a water stop portion that can be in close contact with the inner peripheral surface of the cavity and the outer peripheral surface of the electric wire, and has an extending portion behind the water stop portion. Yes.
Japanese Utility Model Publication No. 7-27069

  In the above case, when the electric wire inserted through the rubber plug is bent, the water stop portion follows and deforms, and a gap is formed between the inner peripheral surface of the rubber plug and the outer peripheral surface of the electric wire, and water is generated from there. There was a risk of intrusion.

  This invention is completed based on the above situations, Comprising: It aims at providing the rubber stopper and waterproof connector with high sealing performance.

  As means for achieving the above object, the invention of claim 1 is inserted into the cavity of the connector housing in a state where the electric wire is inserted, and between the inner peripheral surface of the cavity and the outer peripheral surface of the electric wire. A rubber stopper for taking a seal, which is disposed inside the cavity and has a water stop portion having a portion that can be in close contact with the inner peripheral surface of the cavity and the outer peripheral surface of the electric wire, and the inner side and the outer side of the cavity. An extending portion having an inner peripheral surface that is arranged in a straddle and is capable of closely contacting the outer peripheral surface of the electric wire in the axial direction and having a linear outer peripheral surface parallel to the inner peripheral surface, And a first recess is formed in at least the outer peripheral surface of both the inner and outer peripheral surfaces, and a second recess is formed in a portion of the extension located outside the cavity. And a configuration in which the inner and outer peripheral surfaces are recessed. Characterized in place was.

  According to a second aspect of the present invention, in the first aspect of the present invention, at the end portion of the extension portion, a thick portion is formed that is built up radially outward from the bottom surface of the second concave portion. However, it has characteristics.

  According to a third aspect of the present invention, there is provided a waterproof connector to which the rubber plug according to the first or second aspect is attached, and when the electric wire inserted through the rubber plug is bent, the cavity of the connector housing is It is characterized in that it is set so that the outer peripheral surface of the extension part interferes with the opening edge.

<Invention of Claim 1>
Even if the extension portion follows and deforms when the electric wire is bent, the first recess is formed at least on the outer peripheral surface between the extension portion and the water stop portion. It is possible to suppress the influence of deformation on the surface. In addition, since the second recessed portion is formed in the extending portion on both the inner and outer peripheral surfaces, the deformation amount of the extending portion between the second recessed portion and the first recessed portion can be suppressed to be small. As a result, the deformation of the water stop portion is suppressed with high certainty, and a predetermined sealing property can be maintained.

<Invention of Claim 2>
Since the thick portion is formed at the end portion of the extension portion, it is possible to prevent the end portion of the extension portion from being cut by the electric wire when the electric wire is inserted into the rubber plug.

<Invention of Claim 3>
When the electric wire is bent, the outer peripheral surface of the extension part interferes with the opening edge of the cavity. However, since the outer peripheral surface of the extension part is linear, it is possible to prevent the rubber plug from being cut by interference.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS. The rubber plug 10 of this embodiment is accommodated in a connector housing 90 of a waterproof connector together with a terminal fitting 60 that is caulked and connected to the end of the electric wire 50.

  The connector housing 90 is made of a synthetic resin, and has a cavity 91 penetrating in the front-rear direction, as shown in FIG. A terminal fitting 60 fitted with a rubber plug 10 can be inserted into the cavity 91 of the connector housing 90 from behind. The terminal fitting 60 inserted into the cavity 91 is blocked by a front wall 92 of the cavity 91 and is prevented from coming back backward by a deflectable lance 94 protruding from the inner wall of the cavity 91. A substantially second half portion of the cavity 91 is a rubber plug mounting hole 95 having a circular cross section, and the rubber plug 10 is accommodated by inserting the terminal fitting 60 into the cavity 91. The front wall 92 of the cavity 91 is formed with a tab insertion opening 93 into which the male tab 70 disposed in the mating connector housing enters.

  The terminal fitting 60 is formed by bending a conductive metal plate or the like, and has an elongated shape in the front-rear direction as a whole. The terminal metal fitting 60 is a so-called female terminal metal fitting, and is engaged with and electrically connected to the mating male tab 70 as the two connector housings are fitted. The substantially first half of the terminal fitting 60 is a rectangular tube-shaped main body 61, and the substantially second half of the terminal fitting 60 is an open barrel-shaped barrel portion 62, 63. A stabilizer 64 is formed by cutting and raising the main body 61, and the insertion of the stabilizer 64 into the guide groove 97 cut into the inner wall of the cavity 91 is allowed to be prevented from being erroneously inserted. The stability of the insertion operation of the terminal fitting 60 is ensured by sliding the stabilizer 64 in the guide groove 97.

  The barrel portions 62 and 63 are positioned on the front side to crimp and fix the core wire 51 of the electric wire 50, and the barrel portions 62 and 63 are positioned on the rear side to fix the rubber plug 10 and the sheath 52 of the electric wire 50 by caulking and fixing. It consists of.

  The rubber stopper 10 is made of, for example, silicon and has a cylindrical shape as a whole. As shown in FIGS. 4 and 5, the rubber stopper 10 includes a barrel receiving portion 11, a water stopping portion 12, and an extending portion 13 in order from the front. Is done. Among these, the barrel receiving part 11 and the water stop part 12 are disposed in the rubber plug mounting hole 95 of the connector housing 90, and the extending part 13 is disposed across the rubber plug mounting hole 95. Inside the rubber plug 10, an electric wire insertion hole 14 that penetrates in the front-rear direction along the central axis is formed. The electric wire 50 is inserted into the electric wire insertion hole 14 from the rear, so that the rubber plug 10 is connected to the electric wire 50. The terminal cover 52 is fitted.

  An insulation barrel 63 is wound around the outer peripheral surface of the barrel receiving portion 11, and the rubber plug 10 is held by the terminal fitting 60 by the pressure-bonding force. The barrel receiving portion 11 is thinner than the water stopping portion 12 and the extending portion 13, and extends in the front-rear direction with a substantially constant thickness except for the front end portion. The front end portion of the barrel receiving portion 11 is an annular flange portion 15, and the insulation barrel 63 is prevented from coming off by the flange portion 15.

  The water stop portion 12 is integrally coupled to the rear end of the barrel receiving portion 11 and has a plurality of lips 16 and 17 arranged in parallel at a substantially constant interval in the front-rear direction. The lips 16, 17 are composed of an inner peripheral lip 16 provided around the inner peripheral surface of the water stop portion 12 and an outer peripheral lip 17 provided around the outer peripheral surface of the water stop portion 12. The phase is shifted while partially wrapping in the front-rear direction. When the rubber plug 10 fitted to the electric wire 50 is inserted into the cavity 91, the inner peripheral lip 16 is in close contact with the outer peripheral surface of the electric wire 50, and the outer peripheral lip 17 is in close contact with the inner peripheral surface of the rubber plug mounting hole 95. It has come to be.

  Three lips 16 and 17 are provided in the front-rear direction. The depth of the valley located between the two rear lips 16 and 17 is the depth of the valley located between the two front lips 16 and 17. Accordingly, the substantially latter half portion of the water stop portion 12 is thicker than the substantially first half portion. Further, the valley located between the inner peripheral lips 16 is formed as a flat bottom concave portion 18 in which the inner peripheral surface of the water stop portion 12 is recessed, and is not in contact with the outer peripheral surface of the electric wire 50 even when the electric wire 50 is inserted. It is said. A first concave portion 21 having a semicircular cross section in which the outer peripheral surface of the water stop portion 12 is further recessed is provided immediately after the rearmost outer peripheral lip 17 (position serving as a boundary with the water stop portion 12). Is formed in the direction. The rearmost concave portion 18A is located at a position facing the first concave portion 21 in the thickness direction, and the rearmost concave portion 18A extends longer in the front-rear direction than the other concave portion 18. It has become.

The extension part 13 is integrally coupled to the rear end of the water stop part 12, and is configured by arranging a first recess 21 between the water stop part 12 on the outer peripheral surface side. Both the inner and outer peripheral surfaces of the extending portion 13 are linearly extended in the front-rear direction, and the thickness of the extending portion 13 is such that the inner and outer lips 16 and 17 in the water stop portion 12 are in a natural state (not elastic). It is smaller than the thickness between the tops of the two and larger than the thickness between the bottom surfaces of the inner and outer valleys.
The minimum diameter of the inner peripheral surface of the extending portion 13 (the inner peripheral diameter of the portion excluding the second concave portion 22 and the tapered edge 24 described later) is smaller than the outer diameter of the electric wire 50 in the natural state, and the electric wire is inserted. When the electric wire 50 is inserted through the hole 14, the inner peripheral surface of the extending portion 13 is brought into close contact with the outer peripheral surface of the electric wire 50. On the other hand, the maximum diameter of the outer peripheral surface of the extending portion 13 (the outer peripheral diameter of the portion excluding the second concave portion 22 and the tapered edge 24 described later) is naturally smaller than the inner diameter of the rubber plug mounting hole 95, and the electric wire 50 When the rubber plug 10 fitted into the cable 91 is inserted into the cavity 91 and the electric wire 50 extends straight rearward, the outer peripheral surface of the extending portion 13 is not in contact with the inner peripheral surface of the rubber plug mounting hole 95. Contact.

  A region of approximately one-fourth of the extended portion 13 is an entry region 13A that enters the inside of the rubber plug mounting hole 95 when the rubber plug 10 is inserted into the cavity 91 at a normal depth, and the remaining region An area of approximately three quarters of the rear side is an exposed region 13B exposed to the outside from the rubber plug mounting hole 95 when the rubber plug 10 is inserted into the cavity 91 at a normal depth. In the exposed region 13B of the extending portion 13, a second concave portion 22 having a semicircular cross section is formed in a substantially central portion in the front-rear direction so as to be recessed in the circumferential direction of both the inner and outer peripheral surfaces. The second recesses 22 on the inner and outer peripheral surfaces are set at the same position in the front-rear direction.

  The depth of the second recess 22 on the outer peripheral surface side is substantially the same as the depth of the first recess 21 in the natural state. On the other hand, the depth of the second recess 22 on the inner peripheral surface side is substantially the same as the depth of the second recess 22 on the outer peripheral surface side, and the bottom surface of the second recess 22 is a recess in the water stop portion 12. It is in a position that is further inside the wall thickness than the bottom surface of the portion 18.

  A thick portion 23 is formed at the rear end portion of the extending portion 13 so as to rise in the thickness direction from the bottom surface of the second recess 22. The thick portion 23 has substantially the same thickness as the portion of the extended portion 13 excluding the second concave portion 22, and the inner and outer peripheral surfaces thereof are linear. However, both the inner and outer peripheral surfaces of the rear end of the thick portion 23 (extension portion 13) are formed with notched taper edges 24, and interference with surrounding electric wires 50 and the like is avoided by the tapered edges 24 on the outer peripheral surface side. Then, the electric wire 50 is guided to the electric wire insertion hole 14 by the tapered edge 24 on the inner peripheral surface side.

Next, the operation of this embodiment will be described.
When the electric wire 50 is inserted from behind into the electric wire insertion hole 14 of the rubber plug 10, the electric wire 50 is guided by the taper edge 24, and the thick shape of the thick portion 23 causes the electric wire insertion hole 14 to be inserted. The opening shape is maintained, and the electric wire 50 smoothly passes through the rubber plug 10. The rubber plug 10 through which the electric wire 50 is inserted has a shape that is stretched in the front-rear direction compared to the natural state, and in particular, the thin-walled portion is pulled, and the recessed portion 18A at the tail end of the water stop portion 12 is 2 compared to the natural state. It extends to more than double the length (see FIG. 1).

  Subsequently, the barrel portions 62 and 63 of the terminal fitting 60 are caulked and connected to the end of the electric wire 50, and the terminal fitting 60 is inserted into the cavity 91 of the connector housing 90 from the rear, whereby the water stop portion 12 of the rubber plug 10. Is fitted into the rubber plug mounting hole 95 in a watertight manner. In this state, the outer peripheral lip 17 is in close contact with the inner peripheral surface of the rubber plug mounting hole 95 while being crushed in the thickness direction, and the inner peripheral lip 16 is in close contact with the outer peripheral surface of the electric wire 50 while being crushed in the thickness direction. The seal in the cavity 91 is taken and water is prevented from entering the cavity 91. Further, when the terminal fitting 60 is normally inserted into the cavity 91 in this way, the entry region 13A of the extending portion 13 is loosely fitted into the rubber plug mounting hole 95 and can move along the electric wire 50 within the gap range, and the extension The straight outer peripheral surface of the protruding portion 13 faces the inner and outer sides of the rubber plug mounting hole 95 and is opposed to the opening edge of the rubber plug mounting hole 95. Thereafter, with the fitting of the two connector housings 90, the male tab 70 enters the cavity 91 from the front through the tab insertion port 93, and the male tab 70 is inserted into the main body 61 of the terminal metal fitting 60. Are electrically connected (see FIG. 2).

  From the above state, when a bending force is applied to the electric wire 50 in a direction crossing the insertion direction into the cavity 91, the electric wire 50 is bent and the extending portion 13 having high adhesion to the electric wire 50 is obtained. The wire 50 is deformed following the electric wire 50, and the linear outer peripheral surface of the extending portion 13 interferes with the opening edge of the rubber plug mounting hole 95. At this time, the second recesses 22 on both the inner and outer peripheral surfaces of the extension part 13 are particularly greatly deformed (stretched) due to the thin wall. The amount of deformation in the area in front of the second recess 22 is kept small. In addition, the extension part 13 is elastically compressed on the inner side in the bending direction, and is extended on the outer side in the bending direction.

  Further, the continuity between the extended portion 13 and the water stop portion 12 is partially cut off by the first concave portion 21 and the last concave portion 18A, so that the influence of the deformation of the extended portion 13 is affected. It is suppressed to reach the water stop part 12. Further, when the electric wire 50 is finely shaken due to vibration or the like, the vibration force is absorbed by the extension portion 13 by the thick portion 23 and the first recess portion 21, and the vibration force is propagated to the water stop portion 12. It can be suppressed.

  As described above, according to the present embodiment, the first recess 21 is formed to be recessed between the extension portion 13 and the water stop portion 12, and the second recess 22 is formed to be recessed in the extension portion 13. Therefore, even when the extension part 13 follows and deforms the electric wire 50 when the electric wire 50 is bent, the influence of the extension part 13 on the water stop part 12 can be suppressed, and the water stop part 12 is deformed. Can be prevented. As a result, the sealing action by the water stop portion 12 can be satisfactorily exhibited, and deterioration of the sealing performance can be prevented.

Moreover, since the thick part 23 is formed in the rear-end part of the extension part 13, it can prevent that the rear-end part of the extension part 13 is cut | disconnected by the electric wire 50 at the time of the insertion of the electric wire 50 to the rubber stopper 10. At the same time, the stability of the insertion operation of the electric wire 50 is ensured.
Further, when the electric wire 50 is bent, the outer peripheral surface of the extending portion 13 interferes with the opening edge of the cavity 91, but the outer peripheral surface of the extending portion 13 is linear. Can prevent the rubber stopper 10 from being cut.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) The first recess may be formed not only on the outer peripheral surface of the rubber plug but also on the inner peripheral surface. But in the said Embodiment 1, the last recessed part substantially plays the role of a 1st recessed part.
(2) The outer peripheral surface of the entry area of the extension may be in close contact with the inner peripheral surface of the cavity (rubber plug mounting hole).
(3) The rubber plug may be configured to be connected to a male terminal fitting having a male tab.
(4) The number and arrangement of lips are arbitrary, and are not limited to the first embodiment.

In Embodiment 1 of this invention, the figure which shows the state in which the rubber stopper which penetrated the electric wire was connected to the terminal metal fitting The figure which shows the state where the terminal metal fitting is inserted in the cavity and connected to the male tab The figure which shows the state where the electric wire was bent Cross section of rubber stopper Side view of rubber stopper

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Rubber plug 12 ... Water stop part 13 ... Extension part 21 ... 1st recessed part 22 ... 2nd recessed part 23 ... Thick part 50 ... Electric wire 90 ... Connector housing 91 ... Cavity 95 ... Rubber plug installation hole

Claims (3)

A rubber plug that is inserted into the cavity of the connector housing with the electric wire inserted therethrough and takes a seal between the inner peripheral surface of the cavity and the outer peripheral surface of the electric wire,
A water stop portion that is disposed inside the cavity and has a portion that can be in close contact with the inner peripheral surface of the cavity and the outer peripheral surface of the electric wire;
An extending portion that is disposed across the inside and outside of the cavity and has an inner peripheral surface that can be in close contact with the outer peripheral surface of the electric wire in the axial direction and has a linear outer peripheral surface parallel to the inner peripheral surface And
At the boundary between the water stop portion and the extension portion, a first recess is formed in a recess on at least the outer peripheral surface of the inner and outer peripheral surfaces,
A rubber plug, wherein a second recess is formed on both the inner and outer peripheral surfaces at a portion of the extension portion located outside the cavity.   2. The rubber plug according to claim 1, wherein a thick-walled portion is formed on an end portion of the extending portion so as to be radially outward from a bottom surface of the second recess. A waterproof connector to which the rubber plug according to claim 1 or 2 is attached,
A waterproof connector, wherein an outer peripheral surface of the extension portion interferes with an opening edge of a cavity of the connector housing when an electric wire inserted through the rubber plug is bent.

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